Non-precious metal catalysts (NPMCs) for the oxygen reduction reaction (ORR) are an active subject of recent research on proton exchange membrane fuel cells. In this study, we report a new approach to preparation of self-supported and nano-structured NPMCs using pre-prepared polyaniline (PANI) nanofibers as both nitrogen and carbon precursors. The synthesized NPMCs possess nanoworm structures preserved from the PANI precursor and exhibit high onset potential of 0.905 V vs. RHE and selective activity of nearly four-electron ORR pathways. A significant enhancement in the intrinsic activity and onset potential for the ORR is observed when the Fe content in the precursor is increased from 0 to 3.0 wt.%, while further addition to 10.0 wt.% results in a decrease in the catalytic activity.
Journal of Power Sources, 2013, Vol 225, p. 129-136
Oxygen reduction reaction; Non-precious metal catalyst; Heat-treatment; Activity; Active site